Sheet-feeding apparatus



Oct. 20, 1959 A. EDWARDS ETAL' 2,999,369

I SHEET-FEEDING APPARATUS Fild May 16, 1956 s Sheets-Sheet 1 i F/G./.

INVENTORS Oct. 20, 1959 l A. EDWARDS ETAL SHEET-FEEDING APPARATUS Filed May 16; 1956 s sheets-sum 2 Fla. 2.

lNvEN'roRs /W P M ATTORNEYS.

Oct. 20, 1959 Filed May 16, 1956 A. EDWARDS ETAL SHEET-FEEDING APPARATUS 3 Sheets-Sheet 3 'NVENTORS M W United States Patent SHEET-FEEDING APPARATUS Albert Edwards, Timperley, and Harry Peck, Altrincham, England, assignors to Linotype and Machinery Limited, London, England, a British company Application May 16, 1956, Serial No. 585,350 Claims priority, application Great Britain May 18, 1955 Claims. (Cl. 271-56) This invention relates to sheet-feeding apparatus for printing presses, of the type in which the sheets are transferred from a feed-board to the cylinder on the press by means of a swinging-gripper mechanism, which incorporates gripper fingers for the paper mounted on a cross-shaft which is oscillated about its axis to produce the necessary pendulum movement of the grippers.

The object of the invention is to provide locking means for holding the swinging grippers in an inoperative for ward position, so as to afford easier access to the cylinder, e.g. for the fitting of a blanket.

According to the present invention there is provided sheet-feeding apparatus of the type described comprising in combination: a stop element carried on the cross-shaft for movement therewith, a plunger for engaging the stop when the cross-shaft has reached a position such that the grippers are in a fully-forward position, at which position the plunger acts as a bolt to prevent return movement of the cross-shaft until release of the plunger, and control means for resiliently acting on the plunger to move it selectively to and from its locking position.

The stop may be in the form'of a cam plate having a recess to receive the plunger, the arrangement being such that when the plunger is moved towards its locking position, it rides upon the surface of the plate until the recess comes into register, when the plunger is free to engage in the recess under the action of the spring means, the plate andcross-shaft thereby being locked against continued movement.

The preferred form of control means includes the combination of a spindle, a gear wheel on the spindle in mesh with a rack extending along the plunger, a handle mounted for free rotation on the spindle, and a spring connection between the handle and the spindle. When the handle'is moved between the locking and release positions, it acts through the spring connection to impart a torque to the' spindle which is transmitted by the geared connection into a thrust on the plunger.

The spring connection between the handle and the spindle may consist of a pair of coil springs located between stops in an annular recess of a cap fixed on the.

spindle, one stop being fixed to the cap, and the other stop to the handle.

One embodiment of the invention is illustrated by way of'example, and partly diagrammatically, in the accompanying drawings, in which:

Figure 1 is a side elevation showing the drive for the swinging gripper system and the locking mechanism;

Figure 2 is a longitudinal section on an enlarged scale of the locking mechanism, the section being on the line 22 of Figure 3; and

Figure 3 is a section on the line 33 of Figure 2.

The swinging gripper system serving as a sheet holding and transferring device is carried on a cross-shaft 11 that extends transversely of the machine frame 12. The shaft 11 is oscillated about its axis by means of a rotary edge cam 13, so as to produce a pendulum movement of the swinging gripper system. The cam acts on a roller 14 carried by a lever arm .15 pivoted at 16 to the machine frame. On the free end of the arm 15 is pivoted at 17 the forked lower end 18 of an upstanding link 19. The forked upper end 20 of the link 19 is pivoted at 21 to an arm 22 fixed by a pin 23 on one end of the cross-shaft 11.

The roller 14 is held resiliently to riding contact with the cam 13 by a coil compression spring 24 engaging an arm 25 on the cross-shaft 11.

The gripper system swings with the cross-shaft 11 in the manner of a pendulum between the extreme positions shown at A and B.

In order to lock the gripper system in the position shown at A, where it is in its furthermost position from. the cylinder, the cross-shaft 11 is fitted with a stop mem-..

her in the form of an arcuate cam plate 26. At one end of this plate is a recess 27. A locking plunger or bolt 28 co-operates with the stop plate.

The plunger 28 is mounted for axial sliding movement in a direction parallel with the cross-shaft '11 and opposite to the inside face of the stop plate 26. Along the top of the plunger is formed a rack 29. The rack is engaged by a pinion 30 on a transmission shaft 31 rotatable in a bearing 32.

On a tail portion 33 of the shaft is fitted for free rocking movement a boss 34 for a handle 35. A cap 36 is fixed on the free end of the tail shaft 33. The inside face of the cap is formed with an annular recess 37 in which are fitted two arched coil springs 38 and 39. The springs are separated by two stops 40 and 41. The stop 40 is fixed at 42 to the cap 36, and the other stop 41 is fixed at 43 to the handle boss 34.

By turning the handle 35 in one or other direction about the tail shaft 33, a spring bias is imparted through one or other of the two springs 38, 39 to the shaft 31, tending to move the plunger 28 endwise towards or away from the stop plate 26.

The handle 35 has a shank 45 fixed in the boss 34. From its outer end the shank is forrned'with an axial hole 46, in which is fitted a coil spring 47 held in place by a grub screw 48. On the shank is slidable a sleeve 49 formed at its free end with a hand-knob 50. A removable plug 51 in the knob affords access to the grub screw 48.

The sleeve 49 is retained on the shank by a pin 52. This pin extends through a slot 53in the shank 45. The lower end of the spring 47 bears upon the pin 52, and thereby acts resiliently to hold the handle sleeve 49 down on the shank 45 as shown in Figure 2.

One end of the pin 52 projects from one side of the handle for selective engagement in one or other of two notches 54, 55 formed in the edge of a plate 56 fixed to the machine frame 12. The notches correspond to the on and ofi locking positions of the handle 35.

In the drawings the handle is shown in the oif looking position. When it is wished to lock the swinging gripper system, during the operation of the press, the handle knob 50 is first pulled upwards so as to release the pin 52 from the slot 54. The handle is then swung by hand to engage the pin with the other slot 55 atthe on look ing position. The consequent rotation of the handle boss 34 acts through the stop 39 and coil spring 38 to impart a torque to the shaft 31 in a clockwise direction (as viewed in Figure 3). The plunger 28 is thus urged resiliently by the pinion 30 into engagement with the 0pposed face of the stop plate 26. During each cycle of oscillation of the cross-shaft 11, the recess 27 comes opposite the end of the plunger 28. At this position the plunger enters the recess, and the cross-shaft 11 is thereby locked against return movement, so that the swinging gripper system is held clear of the cylinder, at the position A.

When the handle is moved in the oposite direction to the foif locking position, the shaft 31 is biased for return movement by the spring 39, but the plunger is held in its locking engagement by reason of the frictional grip between the plunger and the end of the recess 27. This grip is momentarily released at the point where the roller 14 is engaged by the peak of the cam 13. Thereupon the plunger automatically springs clear of the recess 27 to an inoperative position.

The angular position B can be adjusted by a set-screw 57 engaging a lug 58 on the cross-shaft 11.

We claim:

1. A sheet feeding apparatus for the printing cylinder of a printing press, comprising a cross-shaft adapted to support a sheet holding and transferring device for swinging movement back and forth between a sheet feeding station and the printing cylinder and adapted to be rotatively operated in synchronism with the operation of said cylinder, and locking means for holding the crossshaft against rotation in a position in which the sheet holding and transferring device is away from the cylin der, comprising a stop member connected to said crossshaft for rotation therewith, a plunger movable into and out of locking engagement with said stop member, a control member movable manually and selectively into two positions, and resilient connecting means between said control member and said plunger acting in one position of said control member to press resiliently said plunger into locking engagement with said stop member and acting in its other position to press resiliently said plunger out of locking engagement with said stop member.

2. A sheet feeding apparatus as described in claim 1, wherein said control member is in the form of a handle supported for angular movement about an axis selectively into its two positions.

3. A sheet feeding apparatus as described in claim 1, wherein said resilient connecting means comprises a transmission shaft on which said control member is mounted, a pinion on said transmission shaft, and a rack secured to and extending along said plunger and meshing with said pinion.

4. A sheet feeding apparatus as described in claim 1, wherein said resilient connecting means comprises a pair of coil springs, and means operable when said control member is in one position for stressing one of said springs and for transmitting the stress from the latter spring to said plunger to spring-bias said plunger in a direction to effect its locking engagement with said stop member and operable when said control member is in its other position for stressing the other spring and for transmitting the stress from the latter spring to said plunger to spring-bias said plunger in a direction to effect its release from said stop member.

5. A sheet feeding apparatus as described in claim 1, wherein said resilient connecting means comprises a transmission shaft, a pair of coil springs'arcuated about the axis of said transmission shaft, and means operable when said control member is in one position for stressing one of said springs and for transmitting the stress from the latter spring to said plunger to spring-bias said plunger in a direction to effect its locking engagement with said stop member and operable when said control member is in its other position for stressing the other spring and for transmitting the stress from the latter spring to said plunger to spring-bias said plunger in a direction to efiect its release from said stop member.

6. A sheet feeding apparatus as described in claim 1, wherein said control member is in the form of a handle mounted on said shaft for selective movement about its axis, and wherein said resilient connecting means comprises a transmission shaft, a pair of coil springs arcuated about the axis of said transmission shaft and arranged in series, a stop rigid with said transmission shaft and extending between one pair of opposed ends of said springs, and a stop rigid with said control member and extending between the other pair of opposed ends of said springs, whereby when said control member is in one position, it stresses one of said springs and resiliently biases said transmission shaft for rotation in one direction, and when said control member is in another position, it stresses the other spring and resiliently biases said transmission shaft for rotation in the opposite direction.

7. A sheet feeding apparatus as described in claim 6, wherein said resilient connecting means comprises a cap affixed to said transmission shaft for rotation therewith, and has an annular recess housing said coil springs, one of said stops being afiixed to said cap, the other stop being secured to the hub of said control member.

8. A sheet feeding apparatus as described in claim 6, wherein said resilient connecting means comprises a pinion on said transmission shaft and a rack secured to and extending along said plunger and meshing with said 'pinion.

9. A sheet feeding apparatus for the printing cylinder of a printing press, comprising a cross-shaft adapted to support a sheet holding and transferring device for swinging movement back and forth between a sheet feeding station and the printing cylinder and adapted to be rotatively operated in synchronism with said cylinder and locking means for holding the cross-shaft against rotation in a position in which the sheet holding and transferring device is away from the cylinder comprising a stop member connected to said cross-shaft for rotation therewith, a bolt for engaging said stop member to prevent rotation of thecross-shaft, a control member movable between two positions, a pair of springs, a transmission between said springs and said bolt, means operable when said control member is in one of said positions for stressing one of said springs and for transmitting the stress of said spring to said transmission to urge said transmission for operation in one direction, and means operable when said control member is in its other position for stressing the other spring and for transmitting the stress of the latter spring to said transmission to urge said transmission for operation in an opposite direction.

10. A sheet feeding apparatus as described in claim 9, wherein said bolt is in the form of a plunger and wherein said transmission comprises a pinion on said transmission shaft and a rack secured to and extending along said plunger and meshing with said pinion.

References Cited in the file of this patent UNITED STATES PATENTS 1,790,465 Dudley Jan. 27, 1931 2,339,117 Staples et al. Jan. 11, 1944 2,727,609 Kanemoto Dec. 20, 1955 

